package filter;

import pojo.User;

import javax.servlet.*;
import javax.servlet.annotation.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

@WebFilter(filterName = "LoginFilter",urlPatterns = "/*")
public class LoginFilter implements Filter {
//    过滤器初始化
    public void init(FilterConfig config) throws ServletException {
    }
//    销毁过滤器

    public void destroy() {
    }
// 执行过滤
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws ServletException, IOException {
//        chain.doFilter(request, response);
//        类型转换
        HttpServletRequest req=(HttpServletRequest)request;
        HttpServletResponse resp=(HttpServletResponse)response;
//        处理特殊情况，登录、注册、静态文件
        String [] urls={"/login.jsp","/register.jsp","/css","/js","/login","/user","/verifyCode"};

        String uri=req.getRequestURI();
        for (String u: urls){
            if (uri.contains(u)){
                chain.doFilter(req,resp);
                return;
            }
        }







//        检查是否登录
        HttpSession session= req.getSession();
        User user=(User) session.getAttribute("LOGIN_USER");
        if (user!=null){
//            已登录放行
            chain.doFilter(req,resp);
        }else {
            request.setAttribute("LOGIN_MSG","您尚未登录，请登录");
            request.getRequestDispatcher("/login.jsp").forward(req,resp);
            return;
        }
    }
}
